Fluid pressure devices operated by hydraulic pressure or pneumatic pressure are known, particularly for expanding tubes such as those used in air conditioning coils and the like. Several hydraulic devices have been developed which are suitable for tightly gripping one end of an elongated tube while simultaneously delivering a tube expanding fluid. Among these are U.S. Pat. Nos. 3,505,846; 3,813,751, 3,962,769; and 4,189,162.
None of these patents describe devices which are suitable for use with other hydraulic fittings such as ferrules. When tubes are to be connected with this type of fitting, a ferrule is crimped on to the outside of a tube. A nut is placed behind the ferrule and a mating fitting is fastened to it. In this manner, two tubes can be joined.
One of the problems which is encountered in the assembly of ferrule junctions is the need to test the seal of the tube and ferrule junction before the unit is assembled without harming the integrity of the junction. Currently, no simple and efficient device exists to permit this testing without actually destroying or at the least weakening the junction.
The only prior art devices which are used currently available to test the junction of ferrules to tubes are incapable of making such a test without causing serious damage to the ferrule junction because those devices operate directly on the junction or joint between the ferrule and the tube. This junction may only be about 0.002 inches in length, and cannot be disturbed without being destroyed.
Accordingly, it would be of great advantage in the art if a device could be provided for testing the junction of a ferrule and tube without destroying the integrity of that junction. It is an object of this invention to provide a device for obtaining this advantage.
Another advantage in the art would be obtained if the testing of ferrule tube junctions could simulate the same torque or force to which the junction will be subjected. This is also an object of this invention.
Other objects will appear hereinafter.